Tamping machine with silent friction grip



July 21, 1925. 1,546,993

G. W. PAPK E TAMPING MACHINE WITH SILENT FRICTION GRIP Filed April 7, 1924 2 Sheets-Sheet 1 lzvvz/v TO/i. GODFREY W. PHFKE July 21,1925. 1,546,993

G. W. PAPKE TAMPING MACHINE WITH SILENT FRICTION GRIP Filed April 1924 2 Sheets-Sheet 2 1 /j i eoarmsr w. PEP/TE.

Patented July 21, 1925.

GODFREY W. PAPKE, OF MINNEAPOLIS, MINNESOTA.

'IAMPING MACHINE SILENT FRICTION GRIP.

Application filed April 7, 1924. Serial No. 704,635.

To all whom it mayoonoern:

Be it known that I, GODFREY W. PAPKE, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Tamping Machines with Silent Friction, Grips; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which itappertains to make and use the same. This invention relates to a concrete tamping machine, such as now commonly used to make concrete blocks of various kinds.

' Such machines employtampers which are reciprocated to tamp the concrete when contained in a mold box inwhich the block is formed. It isan object of this invention to provide a tampin machine having a tamper carried by a plunger rod, together with friction means adapted to grip said plunger rod to raise the same and the tamper and to release said rod.

It is a further object of the inventio to provide a tamping machine having such a tamper and plunger rod, together with a reciprocating cross head carrying friction means and having operating means for positioning the friction means in gripping and releasing position, whereby the plunger rod and tamper will be raised and dropped by the movement of the crosshead.

It is another object. of the invention to provide such a tampingmachine having a tamper and plunger rod carrying thesame,

a frame, a reciprocating cross head, friction means disposed in stationary position on the frame adapted to grip the plunger rod at certain times to hold the same elevated, and friction means on the cross head adapted to grip the plunger rod to lift the same and to release the same.

It is a still further object of the invention to provide a tamping machine having a plurality of plungers adapted to be gripped, lifted and released by friction means, togetherjwith spaced means for operating said gripping means synchronously or dlii'erentially.

It is also another object of the invention to provide a novel, simple and efficient gripping means for the plunger rod of the tamping machme.

These and other ob ects and advantages of the invention will be fully set forthin the following description made in connection with the accompanying drawings in which like reference characters refer to the same parts throughout the different views, and in which,

. Fig. 1 is a view in frontelevation of the tamping machine embodying the present inventlon, a portion thereof being shown in vertical section;

Fig.2 is a view in side elevation of the machine shown in Fig. 1, as viewed from the right of Fig.1;

F ig.3 is a view in vertical section taken on the line 33 of Fig. 1, as indicated by the arrows;

Fig. 4 is a vertical section similar to Fig. 3, showingthe parts in a different posit-ion; Fig. 5 is a vertical section. taken on the line 5 5 of Fig. 1, as-indicated by the arrows;

Fig. 6 is a vertical section taken on the line 6 6 of Fig. 4, as indicated by the arrows; 7

Fig. 7 is a horizontal section taken on the line 7-7 of Fig. 4, as indicated by the arrows; and

Fig. 8 is a horizontal section taken on the line 8--8 of Fig. 4:, Figs. 3 to 8 being shown on an enlarged scale.

7 Referring to the drawings, the front part of the tamping machine is illustrated comprising the vertical frame members 1 in which are connected side plates 2 forming a part of a hopper of the machine and to the front of which are secured by the angle members 8 and 4, a pair of oppositely dis: posed channel members 5. The channel members have bolted to the rear sides thereof at their top ends, bearings 6 in which is journaled a shaft 7 extending between said bearings andto the outer sides thereof and having crank disks 8 keyed thereto at its ends. At one end of the shaft which is extended outward farther than the other end, a pulley 9 is secured being disposed between one disk 8 and one of the bearings 6. The crank disksS have projecting crank pins 8 adjacent their. edges towhich are pivoted the upper ends of pitmen 10, said pitmen being pivotally connected at their lower ends to a cross bar 11 extending the rebe tween in front of the channel members 5. The plate '2 and frame members 1 have projecting forwardly therefrom at each side of the machine, angle plates 12 and a pair of oppositely disposed angle bars 13 are bolted to and extend between the members 12 said bars 13 being spaced to form a guideway. Spacing blocks let are secured between the angle members 13 by headed and nutted bolts 15, said blocks forming a plurality of rectangular passageways or guideways between the bars 13 and a plunger rod 16 is guided in each one of said guideways. lVhile any desired number of plunger rods may be used, in the embodiment of the invention illustrated, four of these bars are shown, each of which has secured thereto and depending therefrom at its lower end, a tamper 17 shown as connected to the rods by a set screw 17. The bar 11, as readily will be seen, is adapted to be reciprocated by the crank disks 8 and pitmen and forms a cross head. Adjacent the top of the channels 5, a bar 18 is secured thereto and extends therebetween, being bolted in stationary relation to said channels. The bars 11 and 18 have secured thereto friction gripping and releasing means for the plunger rods 16, there being a gripping and releasing mechanism for .each of said plunger rods. Said friction gripping mechanisms are quite similar and each comprises a bar 19 disposed at the rear of plunger rod 16 and having a fibre friction shoe 19 bolted thereto. Another bar 20 similar to bar 19 is disposed at the opposite side of the plunger rod 16 and has a fibre shoe or friction plate 2O engaging the opposite side of the plunger rod 16. The members 19 and 20 are connected at each side and adjacent their top and bottoms by links pivoted thereto on horizontal axes. The bars 19 and 20 which are carried by bar 18 are connected at their lower ends by links 21 and at their upper ends by links 22, said links passing along the sides of said bars and along the sides of plunger bar 16. The links 22 are extended rearwardly and each one has pivotally connected at its rear end a link 23, the links 23 extending downwardly and being pivoted at their lower ends at each side of an arm 24S projecting rearwardly from a lever arm 24- whi'ch is secured to a shaft 25 extending across the machine between the channels 5 and journaled in bearings secured thereto. The levers 24: which are adjacent the channel members 5 have short forwardly projecting arms to which are pivoted the upper ends of links 26 which extend downwardly and rearwardly and are connected at their lower ends to an angle bar 27 extending between the channels 5 and guided for vertical movement between the flanges of said channels. Tension springs 28 are connected to the ends of the pivot passing through the forward ends of the link '22 and are connected at their other ends to the pivot passing through the rearward ends of links 21. The pivots connecting the links 21 and 22 which carry the springs are shown in Fig. 6 and comprise a stud 29 having a cylindrical central portion of uniform diameter extending through the blocks 19 and 20 and having reduced threaded portions at their outer ends which receive the links 22. Nuts are placed on the threaded portions adjacent said links and small sleeves 30 are placed over the threaded portions and are surrounded by the looped ends of springs 28. Said sleeves 30 are held in place by outer nuts placed on the threaded portions of stud 29. The pivots 31 which have no springs connected thereto are similar to the pivots 29 except that the sleeves 30 and outer nuts are omitted, said pivots being correspondingly shorter. The bars 19 and 20 of the gripping mechanism carried by the bar 11 are connected at their upper ends by links 32 and at their lower ends by links 33, said links and bars being connected by studs 29 and 31 already described. Springs 28 similar to the springs 28 already described, extend between the studs 29 at each side of the bars 19 and 20. The links 82 are extended rearwardly and then bent downwardly at an angle slightly less than a right angle and have sleeves 32 secured therebetween adjacent their bend by bolts 32. The links 82 also have at their ends pivot pins 34 extending therebetween and held in place by cotter pins. The links 33 are also extended rearwardly and pivoted by means of the pins 35 to the forward end of a block 36, the pivot pins 35 also being held in place by cotter pins. Block 36 has adjacent its rear end an L-shaped slot 36 extending therethrough, the vertical arm of \Vl'llCll is disposed toward the forward portion of said member. The rod 25 projects at one side of the machine beyond one channel member 5 and has secured thereto a hand lever 37. It is desirable at certain times to lock this lever and the bar 25 against oscillatory movement and for this purpose a dog 40 is secured to the bar 25 just outside of channel members 5 having a projecting tooth adapted to seat against the to of an angle lever 41 pivoted at 42 to the channel member 5. The horizontal arm of lever 41 projects forwardly beyond the channel 5 and carries an adjustable set screw 43 equipped with a suitable jamb nut. A coiled tension spring 44 is connected to the pivot 42 and to the upper arm of lever ll tending to hold the same in position to be engaged by the tooth on dog l0. An angle bar 45 extends between channel members 5, being secured thereto and is pierced at intervals by headed and nutted bolts passing through a bar 16 disposed parallel to the vertical flange of angle 45. Spaced blocks 47 are clamped between the bars 45 and 4G and have plates at their upper ends contacted by adjustable screws 48 extending crete discharge therein from the front of the hopper formed by plates 2. Power will be appliedto the pulley 9 by a suitable belt.

connected to a GOIIVBIllGDt source of power and said pulley and shaft 7 will be rotated. The crank disks8 are thus rotated and the cross head llis continuously reciprocated.

The bars 19 and 20 with their springs 28 form a friction gripping means which, when r in the positionshown at the top of Fig. 4, or atthe-bottomof Fig. 3, is in gripping position. In this position, the links 21 and 22or 32 and 33, respectively, extend at an acute angle to the longitudinal edges of the blocks 19 and 20. The springs 28 draw the bars '19 and 20 with the friction shoes thereonltightly againstthe plunger rod 16 and said plunger rod cannot move downwardly between the bars 19 and 20, although it can move upwardly: :VVhen the links 21 and 22 or 32 and 33 extend at right angles to the longitudinal edges of the blocks 19 and 20, the friction gripping means is in released position and the plunger rod 16 can easily move downward between the bars19 and 20 and theirfriction shoes. The springs 28 also hold the links'21 and 22 or,32 and 33,

respectively, in this position, this position being sort of a dead center position owing to the disposition of the springs 28. The hand lever 37 normally is in its rearward position, as shown in Fig. 2, and when it is inthis position, the grlpping mechanisms are in the position shown in Fig. 4. The

gripping mechanism secured to the bar 18' thus holds the plunger rod 16 in elevated position, as shown in Figs.1 and 2, and theplunger rods 16 and the tamper 17 will re main in its elevated, position until the lever 37 is pulled forwardly. At this time, the gripping mechanisms connected to the cross head 11 are in released position and merely reciprocate on the plunger rod 16- Said lever, however, cannot be pulled forwardly until the'stop lever 41 is moved out of en- I gagement with the dog 40. As the cross head ll i'eciprocates, however, it contacts thelower end of the screw 43 and saidlever 41 is swung away from the 'dog 40 at each reciprocation of said cross head. The lever rocks the shaft 25 so that the link 22 is pulled downwardly to the position shown in Fig. 3.

This movement also moves the link21 and the plungers 16 are released. The plungers- 16 and the. tampers 17 now drop-onto the con- 'crete: inthe mold box. Vhentherod 25 was thus turned, the links 26 are raised, together with the angle bar 27. As the cross head; 11 now descends with the gripping mechanism thereon in the position shownin Fig. 4, the block 36 will strike against the bar 27, as shown in Fig. 3. Block 36, to

gether with the rear end of link 32 will be pushed upwardly and the pivot pin 34 will move into the rear horizontal portion of the L-shaped slot 36". The links 32 and 33 are thus pushed from the dead center position and spring 28 pulls the blocks 19 and 20 with their friction shoes, into gripping frictional relation to the plunger rod 16. As the cross head rises, therefore, the plunger rod '16 will be elevated therewith, together with the tamper 17. lVhen the cross head approaches the upper limit 0f;its movement, the sleeves 32 on the links 32 will contact the blocks 47. This contact will again push the links 32 down so that they will assume the position shown at the bottom of Fig. 4, which istheir releasing position. The plungers 16 are then again released. and the same, together with the tampers 17 again drop on the concrete in the mold box. The plungers 16 and tampers 17 are thus raised with each reciprocation of the. cross head 11 as long as a the lever 37 is held in its forward position. When thelever 37 is released, the plungers 16 will be raised in the next upward movement .of the cross head 11,'and the friction gripping mechanism on the cross bar 18 will hold the plungers in their elevated position.

The friction gripping mechanism on the cross head will have been moved to its releasing position by its contact with the blocks 47 and itiwill then continue to reciprocate on the plunger rod 16 without grippingthe same. When the lever 37 moves to. its rearward position it is again locked by the lever 41 and cannot be moved forward except when cross head 11 contacts the screw 43, as illustrated in Fig. 5. It may here be noted that the friction gripping mechanism also forms guiding means for the plunger rod.

It will be noted that each of the plungers 16 willbe raised for their full stroke of the cross head before being dropped, no matter to what level the tampers 17 have dropped.

In tamping the concrete the tamper-s will all not assume the same position, but, nevertheless, each one Will be raised the samedistance and dropped when the blocks 47 trip the lower friction gripping mechanism.

From the above descrlption it is seen that applicant has provided a simple and effi- I 'cient operating means for the plungers of 37 canthen bepulled forwardly andthis or to be held in raised position. The parts of the device are comparatively few and are very accurate and posltlve in operation.

The machine is being made commercially and has been amply demonstrated in actual practice and found to be very successful and efficient.

It will, of course, be understood that various changes may be made in the form,.de tails, arrangement and proportions of the parts -without departing from the scope of applicants invention, which, generally stated, consists in a device capable of carrying out the objects above set forth, such as shown and described and'defined in the appended claims.

lVhat is claimed is:

1. In a concrete tamping machine, a vertically reciprocating tamper, a plunger rod carrying said tamper, a reciprocating head, friction means on said head for gripping said rod, and means contacted by said friction means in the reciprocation of said head for operating said friction means to grip and release said rod whereby the said rod and tamper are raised and dropped.

2. In a concrete tamping machine, a vertically reciprocating tamper, a plunger rod carrying said tamper, a reciprocating head, friction means on said head forming guiding means for said rod and adapted to grip and release said rod, spaced means for operating said friction means to grip and release said rod whereby said rod and tamper are raised and dropped,

3. A concrete tamping machine having in combination, a frame, a vertically reciprocating head on said frame, a tamper, a plunger rod gripping said tamper, a friction means on said frame, means connecting said head and plunger rod for raising said plunger rod, and means for operating said friction means to grip said plunger rod and hold the same in elevated position.

4;. A concrete tamping machine having in combination, a frame, a vertically reciproeating head on said frame, a tamper, a plunger rod gripping said tamper, a friction means on said frame, a friction means on said head, means for actuating said last mentioned friction means to grip and release said plunger rod to elevate and drop the same respectively, and means for operating said first mentioned friction means to hold said plunger rod elevated. V

5. A concrete tamping machine having in combination, a frame, a vertically reciproeating head on said frame, a tamper, a plunger rod carrying said tamper, a friction means on said frame, embracing said plunger rod and adapted to be positioned in gripping and releasing position, a lever pivoted on said frame and connected to said friction means for moving it to either of said positions, and means for reciprocating said plunger rod in said friction means.

6. The structure set forth in claim 5, said last mentioned means comprising a vertically reciprocating cross head, a friction means carried on said cross head and embracing said plunger rod, means connected to said friction means for moving it either to gripping or releasing position, an upper stop adapted to be contacted by said last mentioned means to move the last mentioned friction means on said cross head to releasing position, and a lower stop adapted to be conta'cted by said last mentioned means to remove said friction means on said cross head to gripping position. a

7. The structure set forth in claim 5, said last mentioned means comprising a vertically reciprocating cross head, a friction means carried on said cross head and embracing said plunger rod, means connected to said friction means for moving it either to gripping or releasing position, an upper stop adapted to be contacted by said last mentioned means to move the last mentioned friction means on said cross head to releasing position, a lower stop adapted to be contacted by said last mentioned means to move said friction means on said cross head to gripping posit-ion, a link connecting said lever and said lower stop whereby when said gripping-means on the frame is moved to releasing position, said lower stop will be moved to operative position, and when said friction means on said frame is moved to gripping position, said lower stop will be moved to inoperative position.

8. In a concrete tamping machine, a tamper carrying plunger rod of rectangular cross section, friction bars contacting opposite sides of said rod, upper links pivotally connected to said bars and connecting the same adjacent their upper ends and disposed at each side of said rod, lower links pivotally connected to said bars adjacent their lower ends and extending at each side of said rod, tension springs at each side of said bars extending from the pivots at the forward end of the upper links to the pivots at the rear end of said lower links.

9. The structure set forth in claim 8, one of said pairs of links being extended rearwardly of said rod toform an operating means, and means engaging said extended links to operate said friction bars.

10. The structure set forth in claim 8, said lower links being extended rearwardly, a block pivoted between the rear ends of said lower links and having an L-shaped slot therein, said upper links being extended rearwardly and bent downwardly at a slightly acute angle, and a pin connecting the lower ends of said upper links and disposed in said slot.

11. A concrete tamping machine having in combination, a plurality of tampers, a plunger rod connected to each tamper, a vertically reciprocating cross head, a friction means for each plunger rod carried by said cross head, an operating member for each friction means adapted to be moved to position said friction means in gripping or releasing position, a common lower stop adapted to be contacted by said operating member, a plurality of upper stops adapted to be contacted by said operating member, and means for differentially setting said upper stops.

1.2. A concrete tampering machine having in combination, a frame, a vertically reciprocating head on said frame, a tamper, a plunger rod carrying said tamper, a friction means on said frame for gripping and releasing said rod, a lever for setting said friction means in releasing position, a locking means for said lever, and a stop connected with said locking means adapted to be operated by the upper movement of said cross head to release said locking means and permit said lever to be moved so as to set said friction means in releasing position.

13. In a concrete tamping machine, a tamper carrying plunger rod, friction bars contacting opposite sides of said rod, links pivotally connecting said bars and resilient means connecting pivots on each of said bars, said links being adapted to be moved to one position to cause said bars to grip said rod and to another position torelease said rod, said links being held in gripping position by said resilient means.

14:. In a concrete tamping machine, a vertically reciprocable tamper-carrying rod, friction members extending along each side thereof adapted to contact therewith, spaced parallel means connecting said members and adapted to occupy a dead center position extending substantially at right angles to said members and rod, and resilient means moving said members into contacting relation with said rod when out of said dead center position. V

15. A gripping means for the reciprocating bar comprising members disposed upon opposite sides of said bar, spaced parallel links connecting said members and arranged to occupy a dead center position with said members out of gripping relation to said bar, and resilient means tending to draw said members into gripping relation with said bar when out of said dead center position.

16. The structure set forth in claim 15, one of said links being extended to form an operating member for said gripping means, and means for moving said link to move said member to and from dead center position.

' 17. The structure set forth in claim 15, one

of said links being extended to form an operating means for said gripping means, another of said links being extended and connected to said last mentioned link by a lost motion connection adapted to move to different positions when said members are in and out of said dead center position, respectively.

18. A concrete tamping machine having in combination, a frame, a reciprocable tam per carrying plunger bar, means for lifting and dropping said bar adapted tobe placed in operative or inoperative position, means for holding said bar in elevated position adapted to be placed in operative or inoperative position, and means for placing said last mentioned means in operative position and placing said first mentioned means in inoperative position.

19. A concrete tamping machine having in combination, a frame, a reciprocable tamper carrying bar, reciprocable means for gripping and raising and releasing and drop-ping said bar, said means being adapted to be placed in either operative gripping or inoperative non-gripping condition, means on said fame for gripping said bar and holding the same elevated, and means for causing said last mentioned means to grip said bar and for placing said first mentioned means in non-gripping inoperative condition.

20. A concrete tamping machine having in combination, a frame, a reciprocable tamper-carrying bar, reciprocable means for gripping and raising and releasing dropping said bar, spaced upper and lower means moving said first mentioned means, respectively to releasing and gripping positions, means for gripping said bar to hold the same in raised position, and means for rendering said last mentioned means operative and rendering said lower means inoperative.

In testimony whereof I affix my signature.

GODFREY W. PAPKE. 

